The Future of Output

On the horizon are better, cheaper, and larger display screens; higher-fidelity audio using wave-tab e synthesis and three-dimensional sound; and "real-time" video using digital wavelet theory. 3-D technology is bringing three-dimensionality to computer displays and, through VRML software, 3-D "virtual worlds" to users of the World Wide Web.’

As you might guess, the output hardware we've described so far is becoming more and more sophisticated. Let's consider what's coming into view.

Display Screens: Better & Cheaper

Computer screens are becoming crisper, brighter, bigger, and cheaper. For instance, an LCD monitor from NEC that measures 13 inches from corner to corner now has as high a resolution as a conventional 20-inch monitor, The prices of active-matrix screens are becoming more affordable, and those for passive-matrix screens are lower still.

New plasma technology is being employed to build flat-panel screens as large as 50 inches from corner to corner. Using a technique known as microTeplication, researchers have constructed a thin transparent sheet of plastic prisms that allows builders of portable computer screens to halve the amount of battery power required. Another technique, known as field-emission display (FED), also promises to lower power requirements and to simplify manufacturing of computer screens, thereby lowering the cost. All this is good news in an industry in which screens make up about 40% of a portable computer's cost.

Audio: Higher Fidelity

Generally, points out one technology writer, "the sound wafting from the PC has the crackly ring of grandpa's radio—the one he retired to the attic long ago." Yet users' expectations for microcomputer sound are apt to zoom in 1997, when the DVD will be on the market. The DVD, or CD-size digital video disk, can hold an entire movie with terrific audio.

At present, sounds in a PC are merely approximate. The amount of data from real sound is too much for a microcomputer's microprocessor and con­ventional sound card to handle smoothly and quickly. The next generation of PCs, however, will use a technique known as wave-table synthesis, which is much more realistic than the older method. The wave-table is created, using actual notes played on musical instruments, to form a bank, from which digitally synthesized musical sounds can be drawn on and blended. "The quality of sound you can get from a wave-table is astonishing," says a Yamaha executive. "For a few hundred dollars' worth of add-ons, you can do things on your PC now that 10 years ago musicians in the best studios in the world could not have done."

Sound quality will also be boosted by improvements in amplifiers on sound cards and in speakers. Finally, several companies (SRS Labs, QSound Labs, Spatializer Audio Laboratories) are developing so-called 3-D sound, using just two speakers to give the illusion of three-dimensional sound. Unlike conventional stereo sound, "3-D audio describes an expanded field of sound—a broad arc starting at the left ear and curving around to the right," one writer explains. "In a video game, for example, that means the player could hear an enemy jet fighter approach, take a hit, and explode somewhere off his or her left shoulder." The effect is achieved by boosting certain fre­quencies that provide clues to a sound's location in the room or by varying the timing of sounds from different speakers.

Video: Movie Quality for PCs

Today the movement of most video images displayed on a microcomputer comes across as fuzzy and jerky, with a person's lip movements out of sync with his or her voice. This is because currently available equipment is capa­ble of running only about eight frames a second.

New technology based on digital wavelet theory, a complicated mathe­matical theory, has led to software that can compress digitized pictures into fewer bytes and do it more quickly than current standards. Indeed, the technology can display 30-38 frames a second—"real-time video," giving images the look and feel of a movie. Although this advance has more to do with software than hardware, it will clearly affect future video output. For exam­ple, it will allow two people to easily converse over microcomputer connec­tions in a way that cannot be accomplished easily now.

Дата добавления: 2015-11-14